thermostatic valve - quick question about tails

[dandt]

Hello
Ive bought a set of regis theromstatic valves from B and Q and the two tails are slightly different:
One screws in further and does not have a contour that keeps nut on (ie the nut slides on and off)
The other does not screw in (to rad) as far because of design of end of thread and also the nut is held on (cannot be slid off)
After some thought I have fitted them so that thermo valve is slightly further from rad ie using 2nd fitting which is slightly longer because of design
I dont suppose it makes a lot of difference..
instructions did not mention it and for a non expert like me it would have been better if parts were identical so no decision to be made
Any thoughts?

Also
I am replacing a radiator after fitting new kitchen. I cut the supply pipes near ceiling and cant remember which one led to original thermostatic valve
Does it matter which I use? (ie can a radiator have its valves swap sides and still retain control or if wrong would the radiator remain permanently hot ie water getting to it before valve can act) sorry if this seems a thick question

many thanks

Ps despite this stupidity I am able to do the job (please don't tell me to get someone in). Ive done plumbing for two kitchens but i have never replaced a radiator before

 

[kevplumb]

Ive bought a set of regis theromstatic valves from B and Q and the two tails are slightly different:
One screws in further and does not have a contour that keeps nut on (ie the nut slides on and off)
The other does not screw in (to rad) as far because of design of end of thread and also the nut is held on (cannot be slid off)
After some thought I have fitted them so that thermo valve is slightly further from rad ie using 2nd fitting which is slightly longer because of design
I dont suppose it makes a lot of difference..
instructions did not mention it and for a non expert like me it would have been better if parts were identical so no decision to be made
Any thoughts?

post some pics

Also
I am replacing a radiator after fitting new kitchen. I cut the supply pipes near ceiling and cant remember which one led to original thermostatic valve
Does it matter which I use? (ie can a radiator have its valves swap sides and still retain control or if wrong would the radiator remain permanently hot ie water getting to it before valve can act) sorry if this seems a thick question

most trvs now are bi direstional so it wont matter
as you are gonna use new valves